IC socket and spring means of IC socket

ABSTRACT

An IC socket with good durability that permits electrical tests on the IC to be performed accurately over a long period of time is provided. An elastically deformable metal plate  12  is fixed within a spring accommodating portion  9  of a support board  2.  The metal plate  12  is such that a plurality of spiral cantilevers  19  are formed so as to correspond to bumps  21  of the IC  10,  and the flat tip  19   a  of the spiral cantilever supports an insulative resin film  3.  When the IC  10  is pressed by an IC pressing means  54  and the bump  21  of the IC  10  flexibly deforms the spring means S via the insulative resin film  3,  a contact pressure due to the elastic force of the spring means S occurs in the contact area between the bump  21  and contact pad  11.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to IC sockets used for burn-intests on ICs, such as BGA and LGA, where terminals are formed on a topor bottom surface of their package.

[0003] 2. Description of the Prior Art

[0004] The applicant of the present application have invented an ICsocket 100 as depicted in FIGS. 37-38 and filed a patent application(see Japanese Patent Application No. Hei 10-62228 (62228 of 1998)). ThisIC socket 100 includes an insulative resin film 103 where a circuitpattern (not show) corresponding to a bump (solder ball) 102 of an IC101 is formed; a support board 104 made of an insulative resin forsupporting the insulative resin film 103; and a terminal pin unit 105having its top end connected to said circuit pattern and its bottom endconnected to an electrical test circuit (not shown). On the back side ofthe insulative resin film 103 having the IC 101 disposed thereon isplaced a silicone rubber plate 106. And a pressure member 107 ispivotally attached via a socket body 108 to the top surface of thesupport board 104.

[0005] The IC socket as described above is such that when the IC 101 ispressed downward by the pressure member 107, the bump 102 of the IC 101elastically deforms (dents) the silicone robber plate 106, so that theelastic restoring force of the silicone rubber plate 106 permits thebump 102 of the IC 101 and the circuit pattern to come into contact witha desired contact pressure. The IC socket 100 electrically connects theIC 101 and external electrical test circuit (not shown) via the terminalpin unit 105 and circuit pattern, thereby allowing for accurate burn-intests and so forth.

[0006] However, with the above IC socket 100, if burn-in tests and soforth are repeated at temperatures of about 150° C., the elasticrestoring force of the silicone rubber plate 106 degrades, therebypossibly reducing the contact stability between the bump 12 and circuitpattern. Accordingly, it is desired that an IC socket with greaterdurability be provided.

SUMMARY OF THE INVENTION

[0007] The present invention is invented to meet the market requirementsas described above, and the object of the present invention is toprovide an IC socket with superior durability that can maintain contactstability between the bump and circuit pattern even after it isrepeatedly used more frequently than the prior IC socket.

[0008] A first aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; an IC pressing means, attached to said support board topress the IC terminals against the contact pads of said insulative resinfilm; and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Further, said spring meanscomprises a spiral cantilever formed in an elastically deformable metalplate fixed to the surface of said support board opposite to saidinsulative resin film. The tip of this spiral cantilever presses saidcontact pad against said IC terminal via said insulative resin film.

[0009] A second aspect of the present invention is such that said spiralcantilever is formed so that its height increases toward its tipaccording to the first aspect of the invention.

[0010] A third aspect of the present invention is such that the tip ofsaid spiral cantilever is formed to be flat according to the secondaspect of the invention.

[0011] A fourth aspect of the present invention is such that said spiralcantilever has a dome formed on its tip, said dome protruding towardsaid insulative resin film, and an escape hole that allows flexibledeformation of said spiral cantilever is formed on the surface of saidsupport board opposite to said insulative resin film according to thefirst aspect of the invention.

[0012] A fifth aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surface of saidinsulative resin film opposite to a surface where said contact pads areformed; an IC pressing means, attached to said support board to pressthe IC terminals against the contact pads of said insulative resin film;and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means comprisesa cantilever that is cut and raised from an elastically deformable metalplate fixed to the surface of said support board opposite to saidinsulative resin film, and the tip of the cantilever presses saidcontact pad against said IC terminal via said insulative resin film.

[0013] A sixth aspect of the present invention is such that said metalplate consists of a first metal plate where odd rows of cantilevers areformed and a second metal plate where even rows of cantilever are formedaccording to the fifth aspect of the invention.

[0014] A seventh aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; an IC pressing means, attached to said support board topress the IC terminals against the contact pads of said insulative resinfilm; and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means is suchthat a plate-shaped member is cut and raised from an elasticallydeformable metal plate fixed to the surface of said support boardopposite to said insulative resin film, the tip of the plate-shapedmember is formed so that it can slide over said support board, a curvedportion that protrudes toward said insulative resin film is bent andformed between the tip and root of the plate-shaped member, and thecrest of the curved portion presses said contact pad against said ICterminal via said insulative resin film.

[0015] An eighth aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surface of saidinsulative resin film opposite to a surface where said contact pads areformed; an IC pressing means, attached to said support board to pressthe IC terminals against the contact pads of said insulative resin film;and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means comprisesan opposing pair of cantilevers that are cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film. The tips of this pair ofcantilevers press said contact pad against said IC terminal via saidinsulative resin film.

[0016] A ninth aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surface of saidinsulative resin film opposite to a surface where said contact pads areformed; an IC pressing means, attached to said support board to pressthe IC terminals against the contact pads of said insulative resin film;and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means comprisesa pair of plate-shaped members that are cut and raised, so as to extendin opposite directions to each other, from an elastically deformablemetal plate fixed to the surface of said support board opposite to saidinsulative resin film. The tips of this pair of plate-shaped members areformed so that they can slide over said support board, and a curvedportion that protrudes toward said insulative resin film is bend andformed between the tip and root thereof. The crests of the pair ofcurved portions press said contact pad against said IC terminal via saidinsulative resin film.

[0017] A tenth aspect of the present invention is an IC socket, whichcomprises: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surface of saidinsulative resin film opposite to a surface where said contact pads areformed; an IC pressing means, attached to said support board to pressthe IC terminals against the contact pads of said insulative resin film;and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means comprisesa plate-shaped member that is cut and raised from an elasticallydeformable metal plate fixed to the surface of said supportboard□opposite to said insulative resin film.□This plate-shaped memberhas a raised portion that is raised toward said insulative resin filmand a spring action portion that extends further beyond said raisedportion toward said insulative resin film. The tip of the spring actionportion presses said contact pad against said IC terminal via saidinsulative resin film.

[0018] An eleventh aspect of the present invention is an IC socket,which comprises: an insulative resin film that is elasticallydeformable, where a plurality of conductive contact pads are formed soas to correspond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board that supports a surface of saidinsulative resin film opposite to a surface where said contact pads areformed; an IC pressing means, attached to said support board to pressthe IC terminals against the contact pads of said insulative resin film;and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means. Said spring means comprisesa plurality of cantilevers that are cut and raised from an elasticallydeformable metal plate fixed to the surface of said support boardopposite to said insulative resin film. The tips of those cantileverspress said contact pad against said IC terminal via said insulativeresin film.

[0019] A twelfth aspect of the present invention is an IC socket springmeans for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A spiral cantilever is formed in anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film, and the tip of the spiralcantilever presses said contact pad against said IC terminal via saidinsulative resin film.

[0020] A thirteenth aspect of the present invention is such that saidspiral cantilever is formed so that its height increases toward its tipaccording to the twelfth aspect of the invention.

[0021] A fourteenth aspect of the present invention is such that the tipof said spiral cantilever is formed to be flat according to thethirteenth aspect of the invention.

[0022] A fifteenth aspect of the present invention is such that a domethat protrudes toward said insulative resin film is formed on the tip ofsaid spiral cantilever, and said spiral cantilever may flexibly deformWithin an escape hole formed on the surface of said support boardopposite to said insulative resin film according to the twelfth aspectof the invention.

[0023] A sixteenth aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising; aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminal against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A cantilever is cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film, and the tip of thecantilever presses said contact pad against said IC terminal via saidinsulative resin film.

[0024] A seventeenth aspect of the present invention is such that saidmetal plate consists of a first metal plate where odd rows ofcantilevers are formed and a second metal plate where even rows ofcantilever are formed according to the sixteenth aspect of theinvention.

[0025] An eighteenth aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A plate-shaped member is cut and raised froman elastically deformable metal plate fixed to the surface of saidsupport board opposite to said insulative resin film, the tip of theplate-shaped member is formed so that it can slide over said supportboard, a curved portion that protrudes toward said insulative resin filmis bent and formed between the tip and root of the plate-shaped member,and the crest of the curved portion presses said contact pad againstsaid IC terminal via said insulative resin film.

[0026] A nineteenth aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. An opposing pair of cantilevers are cut andraised from an elastically deformable metal plate fixed to the surfaceof said support board opposite to said insulative resin film, and thetips of this pair of cantilevers press said contact pad against said ICterminal via said insulative resin film.

[0027] A twentieth aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A pair of plate-shaped members are cut andraised, so as to extend in opposite directions to each other, from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film. The tips of this pair ofplate-shaped members are formed so that they can slide over said supportboard, and a curved portion that protrudes toward said insulative resinfilm is bent and formed between the tip and root thereof. The crests ofthat pair of curved portions press said contact pad against said ICterminal via said insulative resin film.

[0028] A twenty-first aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A plate-shaped member is cut and raised froman elastically deformable metal plate fixed to the surface of saidsupport board opposite to said insulative resin film. This plate-shapedmember has a raised portion that is raised toward said insulative resinfilm and a spring action portion that extends further beyond said raisedportion toward said insulative resin film. The tip of the spring actionportion presses said contact pad against said IC terminal via saidinsulative resin film.

[0029] A twenty-second aspect of the present invention is an IC socketspring means for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid□contact pads and an external electrical test circuit; a supportboard that supports a surface of said insulative resin film opposite toa surface where said contact pads are formed; and an IC pressing means,attached to said support board to press the IC terminals against thecontact pads of said insulative resin film; wherein said IC socketspring means presses said contact pads against said IC terminals pressedby said IC pressing means. A plurality of cantilevers are cut and raisedfrom an elastically deformable metal plate fixed to the surface of saidsupport board opposite to said insulative resin film, and the tips ofthose cantilevers press said contact pad against said IC terminal viasaid insulative resin film.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030]FIG. 1 is an exploded, perspective view of an IC socket accordingto a first embodiment of the present invention.

[0031]FIG. 2 is a front, side elevational cross-sectional view of the ICsocket.

[0032]FIG. 3 is a partial enlarged view of FIG. 2.

[0033]FIG. 4 is a plan view of a support board according to the firstembodiment of the present invention.

[0034]FIG. 5 is a cross-sectional view of the support board.

[0035]FIG. 6 is a plan view of an insulative resin film according to thefirst embodiment of the present invention.

[0036]FIG. 7 is a cross-sectional view of the insulative resin film.

[0037]FIG. 8 is a partial enlarged view of FIG. 6.

[0038]FIG. 9 is a plan view of a positioning film, depicting the firstembodiment of the present invention.

[0039]FIG. 10 is a cross-sectional view (a cross sectional view alongline A-A of FIG. 12) of a pressure jig, depicting the first embodimentof the present invention.

[0040]FIG. 11 is diagram depicting the state where the cover of thepressure jig is opened.

[0041]FIG. 12 is a plan view depicting the pressure jig in partialcutaway view.

[0042]FIG. 13 is a cross-sectional view along line B-B of FIG. 12.

[0043]FIG. 14 is a plan view depicting a metal plate according to thefirst embodiment of the present invention.

[0044]FIG. 15 is a partial enlarged view of FIG. 14 (where Y1 portion ofthe FIG. 14 is enlarged).

[0045]FIG. 16 is a front view depicting the metal plate according to thefirst embodiment of the present invention (as seen from Y2 direction ofFIG. 15).

[0046]FIG. 17 is a plan view of a spiral cantilever according to thefirst embodiment of the present invention.

[0047]FIG. 18 is a front view of the spiral cantilever (as seen from Y3direction of FIG. 17).

[0048]FIG. 19 is a front view of a metal plate having a spiralcantilever according to the first embodiment of the present invention.

[0049]FIG. 20 is an enlarged view of principal portions of an IC socket,depicting a second embodiment of the present invention.

[0050]FIG. 21 is a plan view of a metal plate used in the IC socket.

[0051]FIG. 22 is an enlarged cross-sectional view along line C-C of FIG.21.

[0052]FIG. 23 is a plan view of a metal plate, depicting a thirdembodiment of the present invention.

[0053]FIG. 24 is a cross-sectional view along line D-D of FIG. 23.

[0054]FIG. 25 is a plan view where the metal plate of FIG. 23 isseparated into a first metal plate and a second metal plate.

[0055]FIG. 26 is an external perspective view of principal portions of ametal plate, depicting a fourth embodiment of the present invention.

[0056]FIG. 27 is a partial enlarged view of an IC socket that uses themetal plate shown in FIG. 26.

[0057]FIG. 28 is an external perspective view of principal portions of ametal plate, depicting a fifth embodiment of the present invention.

[0058]FIG. 29 is a partial enlarged view of an IC socket that uses themetal plate shown in FIG. 28.

[0059]FIG. 30 is an external perspective view of principal portions of ametal plate, depicting a sixth embodiment of the present invention.

[0060]FIG. 31 is a partial enlarged view of an IC socket that uses themetal plate shown in FIG. 30.

[0061]FIG. 32A is an external perspective view depicting a metal plateaccording to a seventh embodiment of the present invention.

[0062]FIG. 32B is a partial enlarged view of an IC socket that uses themetal plate according to the seventh embodiment of the presentinvention.

[0063]FIG. 33 is an external perspective view of principal portions of ametal plate, depicting an eighth embodiment of the present invention.

[0064]FIG. 34 is a cross-sectional view of a contact pad, depicting aninth embodiment of the present invention.

[0065]FIG. 35A is a view depicting the state where the IC bump isdeformed, i.e., an example of bump deformation where the contact pad ofFIG. 34 is used.

[0066]FIG. 35B is a view depicting the state where the IC bump isdeformed, i.e., an example of bump deformation where a planar contactpad is used.

[0067]FIG. 36 is a view depicting an example where the metal plate ofthe present invention is attached.

[0068]FIG. 37 is a cross-sectional view of a prior art IC socket.

[0069]FIG. 38 is a partial enlarged view of FIG. 37.

DESCRIPTION OF THE PREFEERRED EMBODIMENTS

[0070] Embodiments of the present invention are described in detailbelow with reference to the drawings.

First Embodiment

[0071] As shown in FIGS. 1-2, an IC socket 1 of the present embodimentincludes: a support board made of an insulative resin material (forexample, polyether imide) in plate shape; a metal plate fixed onto thesupport board; an insulative resin film 3 superimposed over the metalplate and over said support board 2; a positioning film 4 superimposedover the insulative resin film 3; and a pressure jig 5 superimposed overthe positioning film 4. It should be appreciated that said support board2, insulative resin film 3, positioning film 4, and pressure jig 5 arecollectively tightened in place by clamping means 8 comprised of screws6 and nuts 7.

[0072] As shown in FIGS. 1, and 6 to 8, the insulative resin film 3 hasa plurality of contact pads 11 formed on a top surface 3 a so as tocorrespond to bumps (terminals) 21 of the IC 10, and also has a circuitpattern 13 formed thereon extending from the contact pad 11 toward theouter periphery. At the ends of the circuit pattern 13 are fixedterminal pins 15 made of a conductive metal that extend downward throughthe insulative resin film and are engaged with the terminal socket 14 ofthe support board, which is described hereinafter (see FIG. 2). Itshould be appreciated that the insulative resin film 3 is formed by aresin material having heat resistance, durability, and elasticity suchas, for example, polyether imide, polyether sulfone, and polyphenylenesulfide.

[0073] Here, the contact pad 11 and circuit pattern 13 are formed byfirst disposing copper in a predetermined shape on the top surface 3 aof the insulative resin film 3, then plating nickel over the copper, andfurther plating gold, rhodium, or solder over the nickel plating.Further, as shown in FIG. 6, outside the contact pad 11 of theinsulative resin film 3, four positioning holes 18 are formed to matewith the positioning ribs 17 on the bottom surface of the socket body16. Furthermore, outside the positioning holes 18, four holes foraccepting the shafts of the screws 6 are formed. It should beappreciated that all the contact pads 11 in FIG. 6, to which one end ofthe circuit pattern 13 is connected as shown in FIG. 8, is connected toeach of the terminal pins 15 via this circuit pattern 13.

[0074] The support board 2 has a spring accommodating portion 9 formedtherein to accommodate an elastically deformable metal plate 12 at aposition corresponding to the IC 10. The spring accommodating portion 9is a rectangular recessed portion formed on the top surface of thesupport board 2, in which the metal plate 12 is fixed by adhesives orscrews (not shown). Here, the metal plate 12 has spiral cantilevers(spring means) 19 formed at positions corresponding to a plurality ofbumps 21 of the IC 10, wherein the spiral cantilever 19 is formed sothat its height increases toward the tip 19 a thereof. The tip 19 a ofthe spiral cantilever 19 is formed to be flat, and this flat tip 19 apresses the contact pad 11 against the bump 21 of the IC 10 via theinsulative resin film 3. With such a spiral cantilever 19, because itsbeam length may be made longer than a straight cantilever counterpart,it is especially effective when the amount of elastic deformation isincreased. Additionally, with such a spiral cantilever 19, because itstip 19 is flat and its area in contact with the insulative resin film 3is increased accordingly, the bump 21 of the IC 10 and the contact pad11 may be contacted securely.

[0075] The support board 2 also has terminal sockets 14 attached theretofor accommodating the terminal pins 15 at positions corresponding to theterminal pins 15 of the insulative resin film 3. The terminal socket 14is made of a conductive metal, so that the terminal pin 15 is engagedinto the upper socket portion 14 a, while the downwardly protruding pin14 b of the support board 2 is engaged into the attachment hole of theexternal electrical test circuit (not shown).

[0076] It should be appreciated that the support board 2 is formed inplanar shape so that the top surface 2 a can support the back surface 3b of the insulative resin film 3 (see FIG. 7), and on this top surface 2a are formed four positioning holes 23 that correspond to thepositioning ribs 17 on the bottom surface of the socket body 16.Further, outside the positioning holes 23 are formed four holes 24 and25 to accommodate the screws 6 and nuts 7.

[0077] The positioning film 4 is formed of an insulative resin film, asshown in FIGS. 1-3 and FIG. 9, and has a rectangular shaped hole 26formed so as to surround the outermost bumps 21 of the bumps 21 of theIC 10, and this rectangular shaped hole 26 serves to align the IC 10onto the insulative resin film 3.

[0078] It should be appreciated that this positioning film 4 also hasfour positioning holes 27 corresponding to the positioning ribs 17 onthe bottom surface of the socket body 16, and outside the positioningholes 27 are formed four holes 28 for accommodating the screws 6 (seeFIGS. 9 and 10).

[0079] The pressure jig 5 has the socket body 16 fixed onto the supportboard 2 via the insulative resin film 3 and positioning film 4, and acover 31 that is pivotally attached to the socket body 16 to open andclose a rectangular shaped IC acceptance port 30 of the socket body 16,as shown in FIGS. 1-3 and FIGS. 10-13.

[0080] Of them, the socket body 16 has the positioning ribs 17 formed onthe bottom surface thereof, as described above, and the positioning ribs17 are engaged into the positioning holes 27 of the positioning film 4,into the positioning holes 18 of the insulative resin film 3, and intothe positioning holes of the support board 2, thereby ensuring alignmentof the socket body 16 itself, positioning film 4, and insulative resinfilm 3 to the support board 2. Further, the socket body 16 also hasguide walls 32 formed at four corners of the rectangular shaped ICacceptance port 30 to guide the IC 10 to a predetermined position overthe positioning film 4 and insulative resin film 3. The guide walls 32are sloped so as to increasingly widen the IC acceptance port 30 upward,thereby ensuring smooth guidance of the IC 10. Here, the guide walls 32and positioning film 4 serve as positioning means to align the IC inplace.

[0081] On one side of the socket body 16 is formed a cover attachmentportion 33 for pivotally attaching the cover 31. To the cover attachmentportion 33 is attached an arm 34 of the cover 31 so that it may bepivoted via a pivot shaft 35. Furthermore, on the other side of thesocket body 16 is attached a hook 37 that engages with a stepped portion36 of the cover 31, so that it may be pivoted via a pivot shaft 38. Itshould be appreciated that the cover 31 is constantly loaded by a spring40 in the clockwise direction (open direction) in FIGS. 10 and 11. Thehook 37 is constantly loaded by a spring 41 in the clockwise direction(in the direction to close the cover 31) in FIGS. 10 and 11.

[0082] An IC pressure block 42 is attached to the cover 31. The ICpressure block 42 is slidably accommodated within a block accommodatingrecessed portion 43 formed on the bottom surface of the cover 31, asshown in FIGS. 10, 11, and 13, where a shaft 46 is fitted into anattachment hole 45 of tongues 44 formed in pair on both sides of thetop, and both ends of the shaft 46 are slidably engaged into the slottedholes (sleeves) 48 of side walls 47 of the block accommodating recessedportion 43, respectively. Further, above the block accommodatingrecessed portion 43 of the cover 31 is formed a spring accommodatinghole 50, in which a compression coil spring 51 is accommodated. Thecompression coil spring 51 constantly loads the IC pressure blockdownward via the shaft 46 in FIGS. 10 and 13, and presses the bumps 21of the IC 10 against the contact pads 11 of the insulative resin filmvia the IC pressure block 42, thereby contacting the bumps 21 andcontact pads 11 with a desired contact pressure (see FIG. 3).

[0083] Here, under condition where the cover 31 is opened, the ICpressure block 42 causes the shaft 46 to be pressed by the compressioncoil spring 51 and come into contact with the bottom end of the sleeve48. When the cover 31 is closed, the IC pressure block 42 compresses thecompression coil spring 51 to the thickness of the IC 10, so that theshaft 46 slides in the sleeve 48 and the side wall 42 a of the ICpressure block 42 is guided to and slide against the side wall 43 a ofthe block accommodating recessed portion 43.

[0084] It should be appreciated that the IC pressure block 42 has itsbottom surface formed in rectangular shape to mate with the shape of theIC 10, and a rectangular shaped recessed portion 52 is formed in thebottom surface thereof, and outside this rectangular shaped recessedportion 52 is formed an IC pressure surface 53. This IC pressure surface53 presses the top surface of the region corresponding to the bumps 21of the IC 10 (see FIG. 3). Thus, the IC 10 is pressed by the IC pressuresurface 53 of the IC pressure block 42, so that the bumps 21 of the IC10 reliably contact the contact pads 11 of the insulative resin film 3.Here, the IC pressure means 54 is comprised of the cover 31, IC pressureblock 42, and compression coil spring 51.

[0085] Further, a slope wall 55 is formed above the stepped portion 36of the cover 31. Thus, sufficient space for manipulation of the hook 37is secured near the manipulating portion 37 a at the tip of the hook 37,so that the hook 37 may be mechanically or manually manipulated withease.

[0086] With the IC socket so configured, when the hook 37 and thestepped portion 36 of the cover 31 are disengaged, the cover 31 ispivoted clockwise in FIG. 10 by the force of the spring 40, so that theIC acceptance port 30 of the socket body 16 is opened (see FIG. 11). TheIC 10 is then inserted into the IC acceptance port 30 of the socket body16 with the bumps 21 facing down (see FIGS. 1 and 3). Meanwhile, the IC10 is guided along the guide walls 32 of the socket body 16 and placedin a predetermined position over the positioning film 4 and insulativeresin film 3. The outermost ones of the bumps 21 of the IC 10 arealigned by the edge periphery of the rectangular shaped hole 26 of thepositioning film 4 (see FIG. 3). As a result, the bumps 21 of the IC 10are securely brought into contact onto the contact pads 11 of theinsulative resin film 3.

[0087] After the IC 10 is accommodated into the socket body 16, thecover 31 is closed, and as the hook 37 is engaged with the steppedportion 36 of the cover 31, the cover 31 is locked to the upper portionof the socket 16. Then, the compression coil spring 51 is compressed tothe thickness of the IC 10, and the spring force of the compression coilspring 51 acts on the IC 10 via the IC pressure block 42. As a result,the bumps 21 of the IC 10 press the insulative resin film toward thesupport board, thereby flexibly deforming the spiral cantilever (springmeans S). That is, the bumps 21 of the IC 10 and the contact pads 11 areelastically sandwiched by the compression coil spring 51 and spiralcantilever 19, so that the bumps 21 of the IC 10 and the contact pads 11are securely contacted. Here, because the spiral cantilever 19 is madeof an elastically deformable metal, it has an outstandingly greaterdurability than a prior art silicone rubber plate when loading isrepeatedly applied under a temperature condition of about 150□

[0088] With the present embodiment as described above, when the IC 10 ispressed by the IC pressure means 54, the bumps 21 of the IC press theinsulative resin film 3 toward the support board 2 to flexibly deformthe spiral cantilever 19, and the resulting elastic force of the spiralcantilever 19 provides a contact pressure between the bumps 21 andcontact pads 11; even when burn-in tests or the like are performedrepeatedly under a temperature condition of about 150□, the metal-madespiral cantilever 19 will not lose its function as the spring means, sothat electrical tests on the IC 10 can be performed accurately over along period of time.

[0089] Additionally, according to the present embodiment, because aplurality of spiral cantilevers 19 are formed in the elasticallydeformable metal plate 12 in correspondence with the bumps 21 of the IC10, and because the metal plate 12 is accommodated in and fixed to thespring accommodating portion 9 of the support board 2, the rectangularshaped spring accommodating portion 9 may merely be formed in thesupport board 2. That is, the present embodiment facilitates machiningof the support board as compared to an situation where, for example,separate compression coil springs are arranged separately correspondingto a plurality of bumps 21 of the IC 10 and a plurality of holes foraccommodating the compression coil springs are formed separately in thesupport board.

[0090] Furthermore, according to the present embodiment, because aplurality of spiral cantilevers 19 are formed in the elasticallydeformable metal plate 12 in correspondence with the bumps 21 of the IC10, as described above, the parts count can be reduced to facilitateparts control, as compared to a situation where separate spring meansare arranged to correspond to the bumps 21 of the IC 10.

[0091] It should be appreciated that in the above embodiment, the springmeans S may be such that a spiral cantilever 19 is formed in thedeformable metal plate 12 as shown in FIGS. 17-18, and a dome 19 b thatprotrudes toward the insulative resin film 3 (upward in the figure) maybe formed on the tip 19 a of the cantilever 19, so that the dome 19 bmay be brought into contact with the insulative resin film 3. In thiscase, an escape hole 55 is formed in an area of the support board 2corresponding to the cantilever 19 so that the cantilever 19 mayflexibly deform. Even so configured, the durability of the IC socket 1and the spring means S used for this IC socket 1 can be improved in asimilar manner to the afore-described embodiment, while reducing theparts count for the IC socket 1 and facilitating parts control.

[0092] Furthermore, in the above embodiment, the spring means S may besuch that the spiral cantilever 19 is formed in the elasticallydeformable metal plate 12 as shown in FIG. 19, and this cantilever 19 isshaped so that its height increases toward its top, with the tip 19 a ofthe cantilever 19 not being flat. Even so configured, a similar benefitto the afore-described embodiment can be obtained.

Second Embodiment

[0093] FIGS. 20-22 show a second embodiment of the present invention. Asshown in those figures, with the present embodiment, spring means S issuch that a plurality of plate-shaped cantilevers 57 are cut and raisedfrom an elastically deformable metal plate 12 accommodated and fixedwithin a spring accommodating portion 9 of a support board 2 incorrespondence with bumps 21 of an IC 10. Further, the tips 57 a of thecantilevers 57 press contact pads 11 against the bumps 21 of the IC 10via an insulative resin film 3. Here, for the spring means S, as shownin FIG. 21, where two rows of bumps 21 of the IC 10 are arranged on eachof the sides by way of example, two vertical rows, right and left, ofcantilevers 57 are cut and raised symmetrically so as to oppose eachother (see FIGS. 20 and 22). Further, horizontal two rows, top andbottom, of cantilevers 57, which are sandwiched between the two verticalrows, right and left, of cantilevers 57, are also cut and raisedsymmetrically so as to oppose each other.

[0094] According to the present embodiment so configured, in addition toa similar benefit to the first embodiment described above, the formationof the cantilevers 57 as the spring means S is simplified as compared tothe above first embodiment.

[0095] Further, by cutting and raising two rows of cantilevers 57 so asto oppose each other, the tips 57 a of the two rows of cantilevers 57can be brought closer to each other, so that a shorter distance betweenthe bumps 21 of the IC 10 can also be supported.

[0096] It should be appreciated that if the distance between the bumps21 of the IC 10 is longer, two rows of cantilevers 57 may be cut andraised in the same direction, instead of cutting and raising two rows ofcantilevers 57 so as to oppose each other. The angle, θ, at which thecantilever 57 is cut and raised from the metal plate 12 is determined asappropriate in consideration of the amount of flexible deformation ofthe cantilever 57, and other factors.

Third Embodiment

[0097] FIGS. 23-25 show a third embodiment of the present invention. Asshown in those figures, with the present embodiment, an elasticallydeformable metal plate 12 is comprised of a first metal plate 12 a whereodd rows of cantilevers 58 a are formed and a second metal plate 12 bwhere even rows of cantilevers 58 b are formed. The first and secondmetal plates 12 a and 12 b are combined so that an even row ofcantilevers 58 b are positioned between adjacent odd rows of cantilevers58 a, and the first and second metal plates 12 a and 12 b areaccommodated and fixed in a spring accommodating portion 9 of a supportboard 2. It should be appreciated that each of the cantilevers 58 a and58 b has its tip located at a position corresponding to each of thebumps 21 of the IC 10, and this tip presses the contact pad 11 againstthe bump 21 of the IC 10 via the insulative resin film 3.

[0098] According to the present embodiment so configured, because evenrows of cantilevers of the second metal plate 12 b are positionedbetween odd rows of cantilevers 58 a of the first metal plate 12 a, thedistance between the cantilevers 58 a and 58 b can be reduced by half ascompared to the case where cantilevers (58 a or 58 b) are formed in asingle metal plate (12 a or 12 b). Thus, the present embodiment may beapplied to electrical tests on ICs with narrower terminal-to-terminalpitches. Additionally, the present embodiment may, of course, provide asimilar benefit to the above first embodiment.

Fourth Embodiment

[0099]FIGS. 26 and 27 show a fourth embodiment of the present invention.As shown in those figures, with the present embodiment, spring means Scomprises a plate-shaped member 60 that is cut and raised from anelastically deformable metal plate 12, where a tip 60 a of theplate-shaped member 60 is bent so that it can slide over a support board2, and a curved portion 60 c that protrudes upward is bent and formedbetween the root 60 b and tip 60 a thereof. This spring means S is suchthat a crest 60 d of the curved portion 60 c presses the contact pad 11toward the bump 21 of the IC 10 via the insulative resin film 3.Further, as shown in FIG. 27, the tip 60 a of the spring means S is bentin approximate “V” shape, so that the bottom 60 e of this V-shapedportion slides over the support board 2.

[0100] More specifically, in the present embodiment, when the IC 10 ispressed downward by the IC pressure means (not shown), as shown in FIG.27, the bump 21 of the IC 10 presses the curved portion 60 c of theplate-shaped member 60 via the contact pad 11 and insulative resin film3. As a result, the tip 60 a of the plate-shaped member 60 slidesleftward over the support board 2 in the figure, and the curved portion60 c of the plate-shaped member 60 elastically deforms as indicated bythe alternate long and two short dashes line in the figure. And thedeformation-resisting force of this plate-shaped member 60 acts betweenthe bump 21 of the IC 10 and the contact pad 11, so that the bump 21 ofthe IC and the contact pad 11 are securely contacted. It should beappreciated that, in the present embodiment, when the plate-shapedmember 60 deforms, the sliding resistance of the tip 60 a of theplate-shaped member 60 is developed, so that the pressure developedbetween the bump 21 of the IC 10 and the contact pad 11 is greater thanwith a simple cantilever.

[0101] According to the present embodiment so configured, a similarbenefit to the above first embodiment may be obtained. That is, with thepresent embodiment, because the plate-shaped member 60 made ofelastically deformable metal can cause a desired contact pressure to bedeveloped between the bump 21 of the IC 10 and the contact pad 11, thedurability of the IC socket and the spring means S used with this ICsocket can be enhanced. Furthermore, with the present embodiment,because the plate-shaped member 60 is formed from the metal plate 12,the parts count for the spring means S can be reduced to facilitateparts control, as well as simplifying fabrication of the support board2.

[0102] It should be appreciated that the present embodiment may beconfigured so that, when the metal plate 12 is fixed to the supportboard 2 as indicated by the dotted line in FIG. 27, the tip 60 a of theplate-shaped member 60 is slightly separated from the support board 2,and when the contact pad 11 and insulative resin film 3 are slightlypressed downward by the bump 21 of the IC 10, the tip 60 a of theplate-shaped member 60 contacts the support board 2. So configured, thespring force of the plate-shaped member 60 acts in two steps. That is,while the tip 60 a of the plate-shaped member 60 does not contact thesupport board 2, the plate-shaped member 60 acts like a cantilever, sothat the deformation-resisting force of the plate- shaped member 60 isrelatively small. However, after the plate-shaped member 60 contacts thesupport board 2, the sliding resistance developed between the tip 60 aof the plate-shaped member 60 and the support board 2 is added, so thatthe deformation-resisting force of the plate-shaped member 60 isincreased.

Fifth Embodiment

[0103]FIGS. 28 and 29 show a fifth embodiment of the present invention.As shown in those figures, with the present embodiment, spring means Scomprises a pair of cantilevers 61 cut and raised, so as to oppose eachother, from an elastically deformable metal plate 12, and the tips 61 aof the pair of cantilevers 61 are bent, so that the curved surface 61 bat the crest of the bent portion supports the insulative resin film 3.

[0104] The spring means S of the present embodiment so configured issuch that when the IC 10 is pressed downward in the figure by the ICpressure means (not shown), the pair of cantilevers 61 deform to aposition indicated by the alternate long and two short dashes lines, andthe resulting deformation-resisting force acts, via the insulative resinfilm 3, between the contact pad 11 and the bump 21, Thus, with thepresent embodiment, a similar benefit to the above first embodiment mayalso be achieved. It should be appreciated that, in the presentembodiment, because the bump 21 is supported by a pair of cantilevers61, the contact stability between the bump 21 and contact pad 11 isincreased, with an increased contact pressure between the bump 21 andcontact pad 11, as compared to the case where the bump 21 is supportedby a single cantilever.

Sixth Embodiment

[0105]FIGS. 30 and 31 show a sixth embodiment of the present invention.As shown in those figures, spring means S of the present embodiment issuch that a pair of plate-shaped members 62 are cut and raised so as toextend in opposite directions, from an elastically deformable metalplate 12, and the tips 62 a of these plate-shaped members 62 are bent sothat curved portions 62 c that protrude upward are formed between thetip 62 a and root 62 b. Further, the crests 62 d of the curved portions62 c support the bump 21 of the IC 10 via the insulative resin film 3.

[0106] According to the present embodiment so configured, when the IC 10is pressed downward in FIG. 31 by the IC pressure means (not shown), thecrests 62 d of the pair of plate-shaped members 62 are pressed downwardvia the insulative resin film 3. As a result, the pair of plate-shapedmembers 62 flexibly deform to a position indicated by the alternate longand two short dashes lines in FIG. 31, and the tips 62 a are broughtinto contact with the support board 2. Subsequently, when the crests 62d of the curved portion s 62 c of the pair of plate-shaped members 62 isfurther pressed by the bump 21 of the IC 10, the tips 62 a of theplate-shaped members 62 slide over the support board 2, so that theplate-shaped members 62 flexibly deform. Thus, the contact pressurebetween the bump 21 of the IC 10 and the contact pad 11 changes in twosteps. That is, the plate-shaped members 62 act as cantilevers untiltheir tips 62 a are brought into contact with the support board 2,thereby developing a relatively small contact pressure between the bump21 and contact pad 11. Next, when the tips 62 a are brought into contactwith the support board 2, frictional resistance is developed at the tips62 a, so that a relatively large contact pressure is developed betweenthe bump 21 and contact pad 11.

[0107] Thus, with the present embodiment so configured, a similarbenefit to the above first embodiment may also be achieved. It should beappreciated that because a pair of plate-shaped members 62 exert aspring action, the spring means S of the present embodiment develops asignificant spring force as compared to the case where a singlecantilever exerts a spring action.

[0108] It should be appreciated that, in the present embodiment, themetal plate 12 may be fixed onto the support board 2 with the tips 62 aof the plate-shaped members 62 contacted onto the support board 2,instead of separating the tips 62 a of the plate-shaped portions 62 fromthe support board 2.

Seventh Embodiment

[0109]FIGS. 32A and 32B show a seventh embodiment of the presentinvention. As shown in these FIGS. 32A and 32B, spring means S of thepresent embodiment comprises a plate-shaped member 63 that is cut andraised from an elastically deformable metal plate 12, and consists of araised portion 63 a that is bent upward (toward the insulative resinfilm 3) in the figure, and a spring action portion 63 b that extendsfurther upward beyond the raised portion 63 a. The tip 63 c of thespring action portion 63 b is bent downward aslant, and the curvedsurface of the crest 63 d of the tip 63 c supports the insulative resinfilm 3.

[0110] The spring action portion 63 b of the plate-shaped member 63 isbent in approximate “<” shape, and when the IC 10 is pressed downward inthe figure by the IC pressure means (not shown), the spring actionportion 63 b of the plate-shaped member 63 flexibly deform as indicatedby the alternate long and two short dashes line in the figure, andpresses the contact pad 11 toward the bump 21 of the IC 10 via theinsulative resin film 3. Thus, the present embodiment may also offer asimilar benefit to the above first embodiment.

[0111] It should be appreciated that the spring action portion 63 b ofthe plate-shaped member 63 is not restricted to those aspects of theinvention where it is bent in approximate “<” shape, but may be formedin an arc, wherein the insulative resin film 3 may be supported by thecrest of the arc.

Eighth Embodiment

[0112]FIG. 33 shows an eighth embodiment of the present invention. Asshown in FIG. 33, spring means S of the present embodiment is comprisedof four cantilevers 64 that are cut and raised from an elasticallydeformable metal plate 12, where the four cantilevers 64 are all formedso as to extend upward toward their tips, and the tips of the fourcantilevers 64 are brought closer to each other. And the tips 64 a ofthe four cantilevers 64 support the bump 21 of the IC 10 via theinsulative resin film and contact pad (not shown).

[0113] According to the present embodiment so configured, because thetips 64 a of the four cantilevers 64 support the bump 21 of the IC 10,the contact stability of the bump 21 of the IC 10 is improved.Additionally, the present embodiment may also offer a benefit similar tothe above first embodiment.

[0114] It should be appreciated that the four cantilevers 64 are curvedin an arc in the figure, although they are not restricted thereto, andmay also be formed in the shape of a approximately straight line.Additionally, the number of cantilevers is not restricted to four, butthree cantilevers or five or more cantilevers may also be formed.

Ninth Embodiment

[0115]FIG. 34 shows a ninth embodiment of the present invention. Asshown in FIG. 34, the present embodiment is configured so that anincreasingly tapered surface 66 with an opening at top thereof is formedin a contact pad 65, and this tapered surface 66 supports the bump 21 ofthe IC 10.

[0116] According to the present embodiment so configured, the bump 21 ofthe IC 10 deforms on a side 64 where it contacts the contact pad 65, asshown in FIG. 35A, but its bottom 68 remains unchanged. On the otherhand, if the contact pad 11 is flat, the bottom 68 of the bump 21 of theIC 10 deforms as a dent when the contact pressure between the bump 21 ofthe IC 10 and the contact pad 11 is significant (see FIG. 35B). Thus, ifthe deformation of the bump 21 as shown in FIG. 35B is not acceptable,the contact pad 65 of the present embodiment may preferably be used.

[0117] It should be appreciated that in each of the above embodiments,the elastically deformable metal plate 12 may be fixed to the supportboard via a silicone rubber plate 70, as shown in FIG. 36. In so doing,with the cover 31 closed (see FIGS. 10 and 11), if the cover 31 ispushed in beyond the engaged positions of the hook 37 and steppedportion 36, the excess amount of the cover 31 pushed in may be absorbedby the deformation of the silicone rubber plate 70, so that the springmeans S will not be overloaded.

[0118] Furthermore, the spring means S need not be installed inone-to-one correspondence with each contact pad, but may correspond toevery other contact pad.

[0119] The above second through eighth embodiments depict other aspectsof the spring means S that comprises the IC socket according to thefirst embodiment of the invention. Thus, the spring means S disclosed inthe second through eighth embodiments may be used with the IC socket 1in place of the spring means S of the first embodiment.

[0120] As described above, the present invention is configured so thatspring means, such as a plate-shaped member(s) or cantilever(s), isformed in an elastically deformable metal plate, and the tip of thisspring means supports the insulative resin film; as such, when the IC ispressed by the IC pressure means and the IC terminal flexibly deformsthe spring means via the insulative resin film, a contact pressure dueto the elastic force of the spring means is developed at the contactarea between the terminal and contact pad, so that electrical tests onthe IC can be performed accurately over a long period of time, ascompared to a prior art example where a silicone rubber plate provides acontact pressure between the bump and contact pad.

1. An IC socket, comprising: an insulative resin film that iselastically deformable, where a plurality of conductive contact pads areformed so as to correspond to a plurality of IC terminals and a circuitpattern is formed to electrically connect said contact pads and anexternal electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed; an IC pressing means, attached to said supportboard to press the IC terminals to the contact pads of said insulativeresin film; and a spring means for pressing said contact pads againstsaid IC terminals pressed by said IC pressing means; wherein said springmeans comprises a spiral cantilever formed in an elastically deformablemetal plate fixed to the surface of said support board opposite to saidinsulative resin film; and wherein the tip of said spiral cantileverpresses said contact pad against said IC terminal via said insulativeresin film.
 2. The IC socket according to claim 1, wherein said spiralcantilever is formed so that its height increases toward its tip.
 3. TheIC socket according to claim 2, wherein said spiral cantilever has itstop formed to be flat.
 4. The IC socket according to claim 1, whereinsaid spiral cantilever has a dome formed on its tip, said domeprotruding toward said insulative resin film; and wherein an escape holethat allows flexible deformation of said spiral cantilever is formed onthe surface of said support board opposite to said insulative resinfilm.
 5. An IC socket, comprising: an insulative resin film that iselastically deformable, where a plurality of conductive contact pads areformed so as to correspond to a plurality of IC terminals and a circuitpattern is formed to electrically□connect said contact pads and anexternal electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed;□ an IC pressing means, attached to said supportboard to press the IC terminals to the contact pads of said insulativeresin film; and□ a spring means for pressing said contact pads againstsaid IC□terminals pressed by said IC pressing means; wherein said springmeans comprises a cantilever that is cut and□raised from an elasticallydeformable metal plate fixed to the surface of□said support boardopposite to said insulative resin film; and□ wherein the tip of thecantilever presses said contact pad against□said IC terminal via saidinsulative resin film.
 6. The IC socket according to claim 5, whereinsaid metal plate consists of a first metal plate where odd rows ofcantilevers are formed and a second metal plate where even rows ofcantilevers are formed.
 7. An IC socket, comprising: an insulative resinfilm that is elastically deformable, where a plurality of conductivecontact pads are formed so as to correspond to a plurality of ICterminals and a circuit pattern is formed to electrically connect saidcontact pads and an external electrical test circuit; a support boardfor supporting a surface opposite to a surface where said contact padsof the insulative resin film are formed; an IC pressing means, attachedto said support board to press the IC terminals to the contact pads ofsaid insulative resin film; and a spring means for pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein said spring means is such that a plate-shaped member is cut andraised from an elastically deformable metal plate fixed to the surfaceof said support board opposite to said insulative resin film; the tip ofthe plate-shaped member is formed so that it can slide over said supportboard; that a curved portion that protrudes toward said insulative resinfilm is bent and formed between the tip and root of the plate-shapedmember; and the crest of the curved portion presses said contact padagainst said IC terminal via said insulative resin film.
 8. An ICsocket, comprising: an insulative resin film that is elasticallydeformable, where a plurality of conductive contact pads are formed soas to correspond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board for supporting a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; an IC pressing means, attached to said support board topress the IC terminals to the contact pads of said insulative resinfilm; and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means; wherein said spring meanscomprises an opposing pair of cantilevers that are cut and raised froman elastically deformable metal plate fixed to the surface of saidsupport board opposite to said insulative resin film; and wherein thetips of the pair of cantilevers press said contact pad against said ICterminal via said insulative resin film.
 9. An IC socket, comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard for supporting a surface opposite to a surface where said contactpads of the insulative resin film are formed; an IC pressing means,attached to said support board to press the IC terminals to the contactpads of said insulative resin film; and a spring means for pressing saidcontact pads against said IC terminals pressed by said IC pressingmeans; wherein said spring means comprises a pair of plate-shapedmembers that are cut and raised, so as to extend in opposite directionsto each other, from an elastically deformable metal plate fixed to thesurface of said support board opposite to said insulative resin film;wherein the tips of this pair of plate-shaped members are formed so thatthey can slide over said support board, and a curved portion thatprotrudes toward said insulative resin film is bend and formed betweenthe tip and root thereof; and wherein the crests of the pair of curvedportions press said contact pad against said IC terminal via saidinsulative resin film.
 10. An IC socket, comprising: an insulative resinfilm that is elastically deformable, where a plurality of conductivecontact pads are formed so as to correspond to a plurality of ICterminals and a circuit pattern is formed to electrically connect saidcontact pads and an external electrical test circuit; a support boardfor supporting a surface opposite to a surface where said contact padsof the insulative resin film are formed; an IC pressing means, attachedto said support board to press the IC terminals to the contact pads ofsaid insulative resin film; and a spring means for pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein said spring means comprises a plate-shaped member that is cutand raised from an elastically deformable metal plate fixed to thesurface of said support board opposite to said insulative resin film;wherein the plate-shaped member has a raised portion that is raisedtoward said insulative resin film and a spring action portion thatextends further beyond said raised portion toward said insulative resinfilm; and wherein the tip of the spring action portion presses saidcontact pad against said IC terminal via said insulative resin film. 11.An IC socket, comprising: an insulative resin film that is elasticallydeformable, where a plurality of conductive contact pads are formed soas to correspond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board for supporting a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; an IC pressing means, attached to said support board topress the IC terminals to the contact pads of said insulative resinfilm; and a spring means for pressing said contact pads against said ICterminals pressed by said IC pressing means; wherein said spring meanscomprises a plurality of cantilevers that are cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film; and wherein the tips ofthose cantilevers press said contact pad against said IC terminal viasaid insulative resin film.
 12. An IC socket spring means for use withan IC socket, said IC socket comprising: an insulative resin film thatis elastically deformable, where a plurality of conductive contact padsare formed so as to correspond to a plurality of IC terminals and acircuit pattern is formed to electrically connect said contact pads andan external electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed; and an IC pressing means, attached to saidsupport board to press the IC terminals to the contact pads of saidinsulative resin film; said IC socket spring means pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein a spiral cantilever is formed in an elastically deformable metalplate fixed to the surface of said support board opposite to saidinsulative resin film, and the tip of the spiral cantilever presses saidcontact pad against said IC terminal via said insulative resin film. 13.The IC socket spring means according to claim 12, wherein said spiralcantilever is formed so that its height increases toward its tip. 14.The IC socket spring means according to claim 12, wherein said spiralcantilever has its top formed to be flat.
 15. The IC socket spring meansaccording to claim 12, wherein said spiral cantilever has a dome formedon its tip, said dome protruding toward said insulative resin film, andwherein said spiral cantilever flexibly deforms within an escape holeformed on the surface of said support board opposite to said insulativeresin film.
 16. An IC socket spring means for use with an IC socket,said IC socket comprising: an insulative resin film that is elasticallydeformable, where a plurality of conductive contact pads are formed soas to correspond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board for supporting a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; and an IC pressing means, attached to said supportboard to press the IC terminals to the contact pads of said insulativeresin film; said IC socket spring means pressing said contact padsagainst said IC terminals pressed by said IC pressing means; wherein acantilever is cut and raised from an elastically deformable metal platefixed to the surface of said support board opposite to said insulativeresin film; and wherein the tip of the cantilever presses said contactpad against said IC terminal via said insulative resin film.
 17. The ICsocket spring means according to claim 16, wherein said metal plateconsists of a first metal plate where odd rows of cantilevers are formedand a second metal plate where even rows of cantilever are formed. 18.An IC socket spring means for use with an IC socket, said IC socketcomprising: an insulative resin film that is elastically deformable,where a plurality of conductive contact pads are formed so as tocorrespond to a plurality of IC terminals and a circuit pattern isformed to electrically connect said contact pads and an externalelectrical test circuit; a support board for supporting a surfaceopposite to a surface where said contact pads of the insulative resinfilm are formed; and an IC pressing means, attached to said supportboard to press the IC terminals to the contact pads of said insulativeresin film; said IC socket spring means pressing said contact padsagainst said IC terminals pressed by said IC pressing means; wherein aplate-shaped member is cut and raised from an elastically deformablemetal plate fixed to the surface of said support board opposite to saidinsulative resin film, the tip of the plate-shaped member is formed sothat it can slide over said support board, a curved portion thatprotrudes toward said insulative resin film is bent and formed betweenthe tip and root of the plate-shaped member, and the crest of the curvedportion presses said contact pad against said IC terminal via saidinsulative resin film.
 19. An IC socket spring means for use with an ICsocket, said IC socket comprising: an insulative resin film that iselastically deformable, where a plurality of conductive contact pads areformed so as to correspond to a plurality of IC terminals and a circuitpattern is formed to electrically connect said contact pads and anexternal electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed; and an IC pressing means, attached to saidsupport board to press the IC terminals to the contact pads of saidinsulative resin film; said IC socket spring means pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein an opposing pair of cantilevers are cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film; and wherein the tips ofthe pair of cantilevers press said contact pad against said IC terminalvia said insulative resin film.
 20. An IC socket spring means for usewith an IC socket, said IC socket comprising: an insulative resin filmthat is elastically deformable, where a plurality of conductive contactpads are formed so as to correspond to a plurality of IC terminals and acircuit pattern is formed to electrically connect said contact pads andan external electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed; and an IC pressing means, attached to saidsupport board to press the IC terminals to the contact pads of saidinsulative resin film; said IC socket spring means pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein a pair of plate-shaped members are cut and raised, so as toextend in opposite directions to each other, from an elasticallydeformable metal plate fixed to the surface of said support boardopposite to said insulative resin film; wherein the tips of the pair ofplate-shaped members are formed so that they can slide over said supportboard, and a curved portion that protrudes toward said insulative resinfilm is bent and formed between the tip and root thereof; and whereinthe crests of the pair of curved portions press said contact pad againstsaid IC terminal via said insulative resin film.
 21. An IC socket springmeans for use with an IC socket, said IC socket comprising: aninsulative resin film that is elastically deformable, where a pluralityof conductive contact pads are formed so as to correspond to a pluralityof IC terminals and a circuit pattern is formed to electrically connectsaid contact pads and an external electrical test circuit; a supportboard for supporting a surface opposite to a surface where said contactpads of the insulative resin film are formed; and an IC pressing means,attached to said support board to press the IC terminals to the contactpads of said insulative resin film; said IC socket spring means pressingsaid contact pads against said IC terminals pressed by said IC pressingmeans; wherein a plate-shaped member is cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film; wherein the plate-shapedmember has a raised portion that is raised toward said insulative resinfilm and a spring action portion that extends further beyond said raisedportion toward said insulative resin film; and wherein the tip of thespring action portion presses said contact pad against said IC terminalvia said insulative resin film.
 22. An IC socket spring means for usewith an IC socket, said IC socket comprising: an insulative resin filmthat is elastically deformable, where a plurality of conductive contactpads are formed so as to correspond to a plurality of IC terminals and acircuit pattern is formed to electrically connect said contact pads andan external electrical test circuit; a support board for supporting asurface opposite to a surface where said contact pads of the insulativeresin film are formed; and an IC pressing means, attached to saidsupport board to press the IC terminals to the contact pads of saidinsulative resin film; said IC socket spring means pressing said contactpads against said IC terminals pressed by said IC pressing means;wherein a plurality of cantilevers are cut and raised from anelastically deformable metal plate fixed to the surface of said supportboard opposite to said insulative resin film, and the tips of thosecantilevers press said contact pad against said IC terminal via saidinsulative resin film.